Last month while the US band The Roots was launching Hip-Hop Fortnight at the Zenith in Paris, five young people were rapping in La Miroiterie, an artists' squat in Ménilmontant on the other side of the city. They were improvising to an audience of about 100 fans before passing on to "open mic" at a monthly event organised by Stelio and Swan from Réflexion Capitale.

All the new generation hip-hop artists have passed through here, having honed their art in the Battle Arena at the Batofar, a boat on the Seine that serves as a nightclub and music venue, or in the French edition of the End of the Weak (EOW) competition. The final round of the fifth annual EOW event was held on at the Bellevilloise during Hip-Hop Fortnight.

Swan is very keen on the Miroiterie sessions, where the entrance fee is a mere €5 ($6). "When we started out five years ago there was no way a small rap group could play in a Paris bar, even though any rock group could. Rappers could only play in their local community centres or in private venues where they would be charged rental fees of between €800 and €2,000. Here they are free to express what they want and rap their guts out. We're not into the rap business; we're into technique and rhyme. And 15-to 20-year-old kids who are skint can come to the concerts without ruining themselves."

The future of French rap is played out in a room covered in wall-to-wall tags by the MCs who have passed through. The group Expression Direkt, who did the sound track for the 1995 film La Haine by Mathieu Kassovitz about young people in the Paris suburbs, are well aware of that. The group's rappers, Weedy and Kertra, hadn't had a record in eight years and played La Miroiterie before bringing out a new one, Le Dernier Brako. "Open stages like rap battles, are the foundations of hip-hop," said Weedy. "We come to see what the experts think of our new lyrics."

A few days earlier, the French EOW finalists took part in a programme on Canal Street, an offshoot of the French cable TV station Canal+ devoted to urban culture. Young people came from all over France. End of the Weak was launched in the US in 2000 and came to France five years later. It is currently held in nine countries. Eric Durand, alias DJ Keri, who organises the event in France, explained the success of this challenge from his own experience. "I discovered it by chance because I suddenly had to replace a DJ in one of the French qualifying rounds," he said. "It turned out to be a hyper-positive experience, you didn't feel threatened for one minute."

This year there were 11 regional rounds but in 2013 they will be 25. The principle is simple: 30 MCs from each region sign up on Facebook before the event, leaving a possibility for five others to do so at the last minute. Seven qualify after demonstrating their stage presence in just one minute. Then they have several hurdles to pass: written verse over music, a cappella verse, "freestyle bag" on five random objects for three minutes, beat juggling and cypha skills, where two competitors improvise together.

Guizmo has taken part in EOW several times, as well as in Rap Contenders, a merciless battle between two MCs broadcast on the internet. Those battles, brought to a wider public for the first time in 8 Mile, Curtis Hanson's film about Eminem, are impressive. Guizmo believes there's no comparison between rappers and MCs. "Anyone can rap but not everyone can be an MC," he said. "An MC is versatile, he's good in all areas. He can hold the stage and write lyrics that are consistent in form and content. MCing and rapping are two separate environments. Rappers are more into studio performances but they don't amount to much on stage."

Artik and Aladoum, both former EOW winners, have stopped taking part in battles. One night, after heaping too much humiliation on his adversary, Artik was unable to leave the Batofar. "On Rap Contenders you can insult someone's mother and the public applauds. Everyone knows it's not for real. But that wasn't the case in my time. In the Batofar I found myself hemmed in by people who were not happy that I had won and that I'd insulted their city."

Aladoum feels the same way about being locked into a format that prevents him from developing as an artist. "Once the public has got used to seeing you in battles, its difficult to bring on your own stuff because people are shouting all the time, 'Clash him, clash him!', so you become a kind of circus freak and that leaves no room for performance. In EOW we're not pitted against anyone else but ourselves." And that's where the MCs, multipurpose players in the rap world, find the richness of expression that will ensure the future of the genre.